I spent all night trying to come up with a good way to define when it's appropriate and when it's not. But in the end, it's a call for the masses, like with any artform.
Sometimes people love it, sometimes people hate it. It's like all advertising, I guess.
Here's a campaign we did in Hong Kong. I thought it was pretty fun. And that's kind of the point of it.
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(Click for a larger size.)